Using timestampMask macro function to change DatePrompt output

I need convert date from datepromt to 'YYYYMMDD' format without using substring function (it's works slow).

I've tried to use macro like this
#sq(timestampMask(prompt('PrDate'),'yyyymmdd'))#
but it returns QE-DEF-0030 Expression parsing error. DetailsQE-DEF-0021 Date constant '0000-00-00 00:00:00.000000000+00:00' is invalid.RSV-SRV-0042

I tried to make format exactly as $current_timestamp have
#Prompt('PrDate', 'string')# +' 00:00:00.000+00:00'
looks good but
#sq(timestampMask(Prompt('PrDate', 'string') +' 00:00:00.000+00:00','yyyymmdd'))#
ruturns just
00000000

I've tried a lot of combination's with sq(), changing spaces and so on

Also i make column with
#sq(_add_days($current_timestamp;-1))#
and in another try to
#sq(timestampMask(sb('Data Item1'),'yyyymmdd'))#
and get the same result 00000000

Please help me, what I'm doing wrong?
Or maybe there are some other method from changing format?

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